ESS will be entering the competitive, expensive, and lucrative E60 and E63 M5/M6 header market. These headers were designed with the ESS supercharger in mind and will be used on the V2+ and V3 supercharger kits whenever those actually come out. RPI will be carrying these headers which is interesting as they also have a header application for the S85. The difference of course being these are new larger diameter designs with forced induction in mind while all the other headers options available currently are intended for naturally aspirated applications. No word on pricing, but likely not cheap as all S85 headers available are expensive.

-how much do they know about headers?
-And isn't this very late in the game in relation to the S85?

-Not much. Even EvoSport has better reputation in Headers market, and let SuperSprint aside. they are the best.
-if they ask a good price for it, they will sell them easily. and also note this headers is for FI cars, no other FI headers were available and it's the first.

would like some dyno of gains and like to hear how it sounds too! they look like quality pieces

I won't delve into the quality but apparently they are saying these will work great for NA applications too which to me appears they are just trying to sell this to anyone. If these are specifically for forced induction then they will not compare to the quality NA options already on the market that have explored this area. I had custom headers specifically for my forced induction application which provided gains but for NA cars lost power. I don't see how they can do both, they are either for forced induction or not.

I won't delve into the quality but apparently they are saying these will work great for NA applications too which to me appears they are just trying to sell this to anyone. If these are specifically for forced induction then they will not compare to the quality NA options already on the market that have explored this area. I had custom headers specifically for my forced induction application which provided gains but for NA cars lost power. I don't see how they can do both, they are either for forced induction or not.

What happened to your headers? Will you still be using them on the new build?

I've never seen ESS produce any quality exhaust pieces. This is not to say that they can't but they have demonstrated little to no experience in the area. This is likely outsourced.

If one has a E63/E64 M6 or an E60 M5, and if you asked around just a little you would end up with a Supersprint headers anyway. They have the know-how and use a proprietary design for the S85 engine. With that world-class engine I would want to attach the best things in the world to it. If you have to ask who made them, that is not a good thing.

I would assume the diameter of the header tubing. Id assume if you go to big on an NA car you will lose lots of torque,if you go to big there wouldnt be enough velocity. I believe a FI car could run bigger tubing because it has the the sc/turbo producing more flow.

This subject is extremely complex. Header design for NA cars is much more senitive, cylinder filling and exhaust tuning has a lot to do with primary diameter and length. For forced induction, it is easier to mask poor header design because you have a blower shoving air down the cylinders.

In NA applications, the headers actually need to be tuned, literally the header length and diameter are specific for your cam and engine. With a blower setup, usually there is less scavenging taking place and you dont necessarily have to tune the headers the same way. For blown applications, bigger is usually better.

A lot of things. I'm not super experienced with this so someone else with more knowledge on the subject should chime in. @PEI330Ci is likely a good candidate to answer.

Originally Posted by DBFIU

This subject is extremely complex. Header design for NA cars is much more senitive, cylinder filling and exhaust tuning has a lot to do with primary diameter and length. For forced induction, it is easier to mask poor header design because you have a blower shoving air down the cylinders.

In NA applications, the headers actually need to be tuned, literally the header length and diameter are specific for your cam and engine. With a blower setup, usually there is less scavenging taking place and you dont necessarily have to tune the headers the same way. For blown applications, bigger is usually better.

PEI or evolve can give you a better answer.

You called?

With FI, you don't need to look at the exhaust velocity to tune the header, so you can go with as long and as large (cross section) a header as you like. You still will benefit from pulse tuning though, which is where you get into the length of the primary tubes. In this case, equalizing the path lengths to get a consistent response is a good idea, and running a lower order harmonic tuning order, usually makes this easier. For example, it's easier to make 36" long primaries stay within 5% on "centerline" length, than 24" long primaries. The longer the tube with straight sections, the lower the PLD. (Path length difference) The "centerline" is an average of the top and bottom path lengths...which when calculated correctly, accounts for the actual flow path length inside a tube with bends.

Looking at the picture, I would guess that ESS has targeted a 2nd order harmonic versus a 3rd order harmonic that you see on most tubular exhaust systems. This means from a N/A perspective that these headers will have a lower peak torque value than a 3rd order header design. Of course it's all a compromise, because any header is "tuned" to a specific RPM point by design, and the efficiency of this design falls off as you go above or below this point. Until someone builds a variable length exhaust header....this will always be the case....

What's really interesting is when you get into development and testing headers. It's no wonder people call this a black art like I found out years ago. Theories are just theories in this area.

On our S62 header, we had a MAHA dyno right next to the development room. Everytime we made a change we dyno tested the car. Changes that we thought would work did not.

We placed alot of emphasis on equal length primaries and found that the engine just did not care after a certain point. We started by making the primaries longer and longer but keeping a small diameter. Power climbed and climbed under the graph area on the first unequal length design. Interestingly peak power did not change much at all from a short unequal length to the long tube (36") but the power under the curve dramatically changed. We then switched to equal length (took ages!) and absolutely nothing happened anywhere in the power range. Equal length of course scrapped because it was almost 1.5 times more expensive to produce. Our final design was not 100% equal length but did have a step up in size in the primaries (known as step design).

Header design has to be done with testing. You just do not know what is going to work and what will sometimes. Even the best programmes in the world cannot predict everything as we have found out from British motorsport companies.

With the V10 header alot of companies including ourselves remove the primary CAT's and this gives a staggering different through the rpm range. Supersprint's amazing design goes even further with a cyclic F1 style collector. That one I know was tested very very well. On that one, I would like to see if some changes could be made to go further. We shall find out hopefully!

Most people don't actually do any testing. They just 'make it'. This is more true within the german tuning industry. Japanese.... that's where lots of testing goes on and they really share it too.

This is very much the case in the nitrous industry: Lots of product designed, but very little tested. There are cases where I have learned more about a manufacturers product than they have....from testing.

Most of exhaust fabricators seem to be more "packaging specialists" than performance specialists....you get what I mean.